Marine Weather and Tide Forecast for Catalina Foothills, AZ

DISCUSSION
An upper low in the northern Great Basin will move south to along the Arizona/Utah border this evening, across northern Arizona tonight and then into New Mexico on Saturday. This system then shifts eastward into the Great Plains Sunday as high pressure aloft begins to build back in across the desert southwest. High pressure aloft will then prevail across the area through next week.

Lowering heights today and Saturday will result in cooler temperatures across southeast Arizona, with highs in the 70s today and in the mid 60s to lower 70s Saturday in valley locations.
These readings are 7-10 degrees below normal. Near freezing morning lows will occur Sunday morning in the colder eastern valley locations such as the Sulphur Springs Valley, where a few areas could dip to freezing for an hour or two. Breezy conditions continue today to the east of Tucson, with isolated near critical to critical fire weather conditions into the early evening hours tonight east of a Sierra Vista to Safford line. Wind gusts have generally been between 25 and 35 mph, with the Guthrie and Headquarters RAWS sites topping out at 41 mph. However, minimum RH values at most locations have stayed above critical thresholds.

This system will also bring a chance of showers mainly north and east of Tucson tonight through mid-day Saturday, with clearing skies from west to east Saturday afternoon/evening. Precipitation amounts are expected to be light with around a quarter of an inch in the White Mountains, one to two tenths on Mount Graham and Mount Lemmon and a couple of hundredths up to a tenth of an inch in eastern valley locations. 2-3 inches of snowfall will be possible in the White Mountains and on Mount Graham, with 1-2 inches of snow on Mount Lemmon.

As the system pushes east of the region on Sunday, heights begin to rise and high temperatures warm back to near normal. High pressure aloft then builds in across the area next week, with highs warming to 6-8 degrees above normal. Mid to late next week, the gradient tightens up in response to a couple of systems moving to our north, which will result in elevated wind speeds during the afternoon/early evening hours mainly east of Tucson.

AVIATION
Valid through 20/00Z.
FEW-SCT clouds at 5k-8k ft AGL thru 19/01Z, becoming SCT-BKN clouds at 5k-8k ft AGL between 19/01Z and 19/14Z. Aft 19/14Z thru the remainder of the forecast period, clearing skies from west to east across the forecast area. Chance of valley -SHRA/mountain -SHSN between 19/01Z and 19/20Z, primarily north and east of KTUS. SWLY SFC wind at 15-22 kts and gusts to 25-32 kts thru 19/02Z, with the strongest SFC wind east of KTUS in the vicinity of KALK, KDUG and KSAD. Diminishing SFC wind aft 19/02Z and SFC wind generally 12 kts or less between 19/04Z and 19/17Z. WLY/NWLY SFC wind aft 19/17Z, with wind speeds of 10-18 kts and gusts to 18-28 kts thru the end of the forecast period (with the strongest wind speeds in the vicinity of KALK, KDUG and KSAD). Aviation discussion not updated for TAF amendments.

FIRE WEATHER
Isolated near critical to critical fire weather conditions will continue into the early evening hours tonight east of a Sierra Vista to Safford line. Winds gusts have exceeded critical thresholds in a few locations this afternoon, although min RH values have generally stayed above critical values. Cooler temperatures through Sunday morning, with high temperatures today and Saturday 7-10 degrees below normal. There will be a slight chance of light precipitation across mainly the eastern half of the forecast area tonight and Saturday, with higher precipitation chances in the White Mountains. A warming trend then starts Sunday and continues through next week, as high temperatures warm to near normal on Sunday and then 6-8 degrees above normal Monday through Thursday.

TWC WATCHES/WARNINGS/ADVISORIES
None.